IDENTIFICATION OF BACTERIAL SPECIES ON OR IN CREVICULAR EPITHELIAL-CELLS FROM HEALTHY AND PERIODONTALLY DISEASED PATIENTS USING DNA-DNA HYBRIDIZATION

The purpose of this investigation was to identify bacterial species pr esent on or in crevicular epithelial cells in healthy and diseased sit es using DNA probes. In order to achieve this aim, further improvement s were made in the separation of unattached bacteria from those adhere nt to epithelial cells isolated from the human gingival crevice or per iodontal pocket. Then the DNA probes were used to determine the preval ence of detectable DNA from 15 microbial species on or in crevicular e pithelial cells. One sample was taken from a single subgingival site i n each of 51 individuals ranging in age from 19 to 45 years. Samples w ere taken from 27 sites of clinically healthy subjects and 24 samples were taken from subjects having periodontally diseased sites. DNA-DNA hybridization indicated that a majority of epithelial cells from healt hy sites (63%) were in contact with or harbored Streptococcus oralis. On the other hand, species such as Bacteroides forsythus, Prevotella i ntermedia, Capnocytophaga ochracea and Campylobacter rectus were more frequently detected in elevated numbers in periodontally diseased site s, Cluster analysis of the microbial profiles generally aggregated sub jects with and without periodontitis into separate cluster groups, The cluster patterns suggest the possibility that microbial complexes wil l be, in part, determined by the receptors available on the epithelial cells.